Speed cup balancing machine



Mardi 26, 1940- c. w. MCKINLEY ET AL SPEED CUP BALANCINGAM'ACHINE m Tm Mmh 26, 1940. c. w. MCKINLEY ET 2,195,252'

SPEED CUP BALANCING MACHINE I il@ SH01/MAA 3mm/vien, C

UNITED STAT-Es PATENT carton Charles W. McKinley, Lucian ',B. Smith, and

Clarence B..Dinsmore, Flint, Mich., as'signbrs` to General Motors Corporation, Detroit, Mich., a corporation of Delaware.r f

Application Novembcr'l, 1935, Serial Noffl'l()y l woning; (o1. vs -51).

This invention relates to a process and a mapivot 31 moves up'and out of alignment vvithpiv-l chine for balancing a freely swinging element and ots 3i andl 39 and the springs 29 A.function to has been designed particularly for balancing thev vmove the motor toward the other end ofthe maspeed cup of akmagnetic measuring instrument.l f chine assisting the lever in so doing.

The object of the invention is to effect' a more To the motor I9 there is lsecured by fastening 511: accurate balancing of the speed cup, to balance means l a Casting 43. This Casting has a lJIO.-r the cup in a way which shall be permanent, to jecton 45 ci tubular form which supportsa heart save time in the process of balancing, and to 4T Sldibly Secured there@ aS SL43. A11 end lavoid cut and try procedure. l y milling cutter -49 is located within the tubular l A further object, and one useful not'only'in projection 45. At-5i on casting 43 iskfulcrumed a 19": v

this machine but elsewhere, is the provision of Ila disc 53. The disc has an arcuate slot 55 through novel form of oscillating bearing to reducefriction which the projection 45 extends, theslot permitat the bearing support. i ting the rotation of the disc about pin 5I. There` Other objects and advantages will be underis an operating handle 51 secured tothe disc bystood from the following description. fastening means l59. The disc has an axial pin 15 The invention is illustrated in the accompany- 6i projecting from its face. The disc is provided ing drawingsliniwhich: with a cam surface'l63 which surface contacts Fig. 1 is a topplan View offthe machine. with the protruding Surface 01' DOliSOn 65 at the Fig.2 is a perspective of a detail.` j i rear end of head 41. A spring 61 is located be- 00 Fig. 3 is a View partly in elevation and partly in tween a* shoulder 69 of the head 41 and a spacer 20 section substantially as lseen from line'3--3 of 1I` which surrounds thecasting 43 and engages Fig. 1. f said casting whereby the spacer becomes a fixed Fig. 4 is an enlarged partial top plan View. abutmentfor` the spring. L. Fig. 5 is a section on line 5-5 yof Fig. 4. 'j' vA corner block is seen at v13 fastened-to base rI I Fig. 6 is a disassembled perspectiveof a part-of' iny any convenient jway.' A lever arm`11 is piv- 25,.

the machine. oted` at 19 to this block. A spring 8.! anchored Fig. 7 is a sectional view online 1'-1of Figl. at 83 and attached to the lever at 85 biases the y y Fig, 8 is a sectional view of a part of themalever to the position shown byFig. 17. The lever chine, the View being at right angles to that fof hasa tangential rarm 81 to one side of which are v Fig. 3. secured by ascrew89 flat springsQI adapted in 30W Figs. 9a, 9b, 9c are diagrams showing the steps one position of the arm to engagea stop 93 proin the operation. I jecting fromrthe block. A cross head- 95 is nor- Referring byvreference characters to the drawmally held in spaced relation to the tangentialI ings, numeral H is abase shown on a platformln arm 81 by pins 91 secured thereto, projectingl for supporting the various parts of themachinel through the arm land .pressed f orward by the I 35,-

To the base are secured by fastening means |31' springs 9| as best shown in Fig. 5.` Between longitudinally disposed undercut guides-I5 for the pins v at punch 99 projects from the armtj, sliding engagement with the support l1 upon' the.I beingxedly held by a screw lOl. The punch upper concave surface of which rests an electric extends through anopening |93 in cross head 95. motor (see Figure 7). *The fore vand aft move- Corner block 13 has an extension at H15 carry- .Y 40.-. ment of the support I1 similarly carries the elecing an arcuate die H11. This die is intended to be I tric motor I9. Fastening means 2.I securev the.l engaged by the inner bottoni wall of a speed cup motor in position. Rigid with support I1 is anl f of a speedometer, this wall being'shown in Figsjiiv end Wall 23, and ,to the adjacentV endfof .base II.` v.and 5 where it is designated by numeral |09. The l is fastened as by screws 25 an abutment .21`be-f die' m1 .has a hole II I for thepassage of the 145-; tween which and walll23 are coil springs'29 op.- punch 99 after the punch has made anopening erative to move the support :and -motor away yfrom in wall |99, this beingfaccomplishedyby rotating abutment 21. To the Wall 21y is'pivoted at 3| y. .the lever 11 as will be understood from Fig-1.- a lever arm 33, and a'link 35 is pivotedY to ,lever Passing 'through the extension |05 is a thrust 33 at 31 and to Wall 23 at'39. The pivots are pobearing H3 to engage the end of the speed cup 50 sitioned as shown so that when the-..lever isv in spindle H5. This thrust bearing is held yielding the position of Fig. 3 the spring is compressed but, against its stop I I1 by a spring I I9 as is showny by ythe pivot 31 is in alignment with pivots 3|v and i Fig.3. Y 39, whereby the spring is incapable of mOVing the Twov postsv IZI and 23 support a cross bar VI25 v 55 motor. When the. lever 33'is raised and rotated, having spacedvertical walls 121 to whichl are 55vl I- CAD , bearing I3.

secured by fastening means |29 flat plates of `resilient steel the upper edges of which appear cured by fastening means |33 spool supports |35,

the spool supports having opposed lugs |31 carrying pins |39 the adjacent ends ofwhich are tapered for the support of spool-like members I4 I. The parts aredimensioned so that the speed cup spindle when supported onthese spools is axially aligned with thrust bearing `I I3 and the speed cup itself may engage the die |tl'1,:its outer wall surrounding the die as shown in Fig. 4. A Secured to cross ybar |25 by fastening means |43 is a synchronous clock -motor |45 the details of which need not be described. The shaft |41 driven by the motor carries a plural face cam |49 engaging abutments |5| secured to the resilient plates |3I. A box-shaped cover I5! may be secured by screws |53 to the cross bar |25. By this motor cam expedient the two supporting spoolsl are beingmoved alternately toward and from each other. In this way the speed cup is mounted on movable supports which ensure free rotation. 'The support is sure to cause the cup to rotate to an extentsuch as to bring the excess weight at the bottom of the vertical axis of the cup. It is this point of the cup which is to be engaged bythe end cutter I9 when the lever 33 is rotated and the head 41 moved to clampy sitioned as shown and is used to withdraw the chips produced by the cutter as it removes metal `from the speed cup. No invention per se is being claimed for this cleaner and it need not be further described.

The operation is as follows: The spindle of the speed cup is placed with its ends on the spools |4I, one end being in contact with the thrust While Vso mounting the cup the arm 33 is swung back so that the motor I9 is withdrawn andthe head 41 is spaced from the die |01. Arm or lever 11 is being held in inoperative position by its spring 8|. The operation of the synchronous motor moves the spools simultaneously toward and from each other, whereby the speed cup is free to rotate and will rotate so that its heavy part will assume a position in the lower part of its vertical diameter. Lever 11 is then rotated until cross head 85 engages the bottom wall of the cup |09 and a further movement causes the punch tol make a hole in the cup at the horizontal diameter, the` punch entering hole IIIin the die, this movement causing the pins 91 to deilect the springs 9| which operate to release the punching mechanism after the hole has been made; The punch is then swung `back to its inoperative position by the spring 8|. `The hole punched in `the cup disturbs its balance and it swings to a new position of rest wherein the hole moves from the horizontal diameter upwardly. The new position again brings the un-V `balancing weight into the lower part of the vertical diameter, the vibrating supporting spools bel ing relied lon to ensurev the free swinging of the cup. v

When the cup has assumed its new position, the

klever arm 33 is rocked to permit the springs 29 to push forward the motor together with the head `41, the disc 53 and the cutter assembly so that the cup bottom is gripped rmly between the said head and the die |01. In so swinging the lever arm 33 a conventional mercury switch carried `thereby and indicated by numeral |59 closes a circuit through suitable wires IBI, a source of energy (not shown) and both the motor I9 for operating the cutter and the vacuum cleaner motor for the purpose of cutting out metal and removing the chips. v

The depth of metal to be cut is measured by the arc of rotation of the speed cup from the original position of rest to its position of rest assumed after the hole is punched. That depth is determined by a rotation of the arm 51 of the disc 53 until its pointer registers with the punched out hole in the disc. The cam face 63 operates to attain this result. The spring 61 between the shoulder 69 and the spacer 1I normally holds the end of` the head somewhat beyond the end of the cutter, the fastening means 48 permitting a limited movement between the part and the head 41. When thev device is in use this movement of `the-head produces a clearance between the disc 53 and the cooperating surface 65. When the springs 2S push theassembly fore ward the head 41 is stopped against the speed l cup and the pressure `from the springs 1&9 overcomes the spring 61 and the head is moved baci; relatively to the extension sleeve I5 so that the end mill'isfree `to work--on the speed cup. In so moving back, its face 55 engages the cam face 63 of the disc, thus limiting the relative movement. Progressively thinner regions of cam surface 63 contact face S5 as the'disc is rotated in the act of bringing its pointer 6| into registration with the punched Aout hole. As these thinner portions are brought opposite the face 6 5, the head is able vto slide back further to permit an added projection of the mill. In this way' the degree of rotation of arms 51 determines the degree of cutting and does soin proportion to the extent to which the dischas rotated after the hole was punched. p v

The theory may bek made clearer by reference to the diagram. Fig. 9a shows the condition of the speed cup before the `first operation. A degree of unbalance'has caused the cup to rotate freely so that the unbalance marked W2 assumes the position shown. The hole W is then punched out as in Fig. 9b and, as described above, in the horizontal axis.v This is equivalent to adding a mass W1 equal to W in the 'position shown. The disc, after rotating to its new position, then may be balanced by removing a mass W3 from the bottom of the vertical diameter. The amount to be removed may be determined by the expression where Wa-Wm In this equation, where W3 isthe amount of material tok be removed, W is the mass removed by the punch, angle b is the complement of angle a, the latter being -the angle through which the punchedcup rotated after the hole was punched. The cam face on the disc is so shaped that when the disc is rotated to an `extent such that the pointer registers withthe punched hole, the cutter will remove the required amount of material.

The machine thus does away with all cut and try steps ofbalancing, is extremely accurate in its results, `and saves much time.

We claim:

1. "I'he process of giving static balance to an unbalanced element consisting in mounting said elementfor free rotation to localize its unbalanced weight in its vertical axis, removing material from one side of said axis, permitting the element to swing to a new position of rest land removing material to balance the element, the

depth of removal being determined bythe mass of material rst removed and the extent of rotation resulting from such first removal. l

2. The process of balancing an out of balance freely rotatable element comprising removing material from a position in its yhorizontal axis at l one side of its vertical axis, permitting said element to rotate after said removal of material and subsequently cutting material from the bottom of the vertical axis, the depth of cutting being determined by the mass of material rst removed and by the angleof rotation of the element afterl said first removal.

3. The process of giving an unbalanced element a static balance consisting in mounting the element for free rotation whereby its out of bal- 4. The invention dened by claim 3, said mass last removed being determined by the expression" l W3'- Wcos b l Where W is the mass rst removed, W3 the mass to be finally removed, and b` equals the complement of the angle through which the .element rotates after the rst removal.

5. In a machine to give static balance to an and at the same radial distance, and additional manually operable means movable to predetermine the mass ofv material removed by the said other means'to produce in said element a static balance.

6. In combination, first means to support a disc for free rotation about a horizontal axis,

second means positioned adjacent said iirst means f and operable to punch a hole in said disc at a certain radial distance in its `horizontal am's a new position of rest, third means adjacent said first and second means and operable to cut material at the same radial distance from the discs vertical axis', and a fourth means movable to an extent dependent upon the mass of material removed by the second means and by the rotation of thedisc subsequent thereto to determine the mass of material removed by the third means.

7. The invention defined by claim 6, said third means including a motor vand end cutter operated thereby and manually operable means to move' said motor and cutter jointly into opera-` tive position. n

8. Ther invention defined by claim 6, said third means including a motor and end .cutter operated thereby'and manually operable means to move said 'motor and cutter jointly 'into operawhereby said disc may rotate about its axis to tive `position together ywith a switch actuated by the movement of said manually operable means to render said motor operable.

9; The invention defined by claim 6, said second means comprising va manually operable lever having 4an extension, a cross head, pins f carried by said cross head and extending through said extension, yielding means on said extension and acting on said pins to space the cross head and a punch secured to thevextension and extending throughthe cross head.

10. The invention deiined by claim 6, said third vmeans comprising an axially movable electric motor having aA shaft, an end cutter in axial alignment therewith and rotated thereby, sleeve means secured to the motor and surrounding the cutter, a hollow head slidingly surrounding said sleeve and cutter, yielding means to project the end of said head along the sleeve and beyond the cutter, spring means to project said motor and head into Contact with the disc and to thereby overcome said yielding means to produce a reverse movement of the head and bring the cutter into operative position, and said fourth means being operable to vary the limit of the reverse movement of said head. V 1

'l CHARLES W. MCKINLEY. Y

` LUCIAN B. SMITH. l

CLARENCE B'. DINSMORE. 

